1. Field of the Invention
This invention relates to a back supporting device for a motor vehicle seat, and more particularly to a back supporting device for a motor vehicle seat that includes a backrest which is movable on the seat.
2. Description of the Related Art
Referring to FIG. 1, a conventional motorcycle seat 1 is shown to include a driver seat portion 11, a passenger seat portion 12, a luggage frame 13, and a backrest 2 fixed on the luggage frame 13 and disposed immediately behind the passenger seat portion 12. As such, the backrest 2 cannot be used to support a driver's back.